Don't bet on it, that's just a big hole that it can eventually escape from.

Check that you've got the tape tight (putting a tube in the tyre overnight will press it down firmly). If still leaking then it likely is the valve. I've had mastic round the last couple I fitted, or else a couple of shims cut out of old inner tube to help it seat into the hole might do it

As Scardeypants says, if it's leaking from the base of the valve it has nowt to do with the tyres.

It will either be the valve seal itself or, more likely, the tape somewhere. Air that gets through the tape will invariably exit via the valve hole being the path of least resistance. Try overlaying it with leccy tape & see if that does the trick.

What pressure have you pumped them up to, to try to get them onto the bead? Use plenty of lubricant and you may have to pump them up to nearer 60psi together them seated. I sometimes put the wheel on the other side of the garage door from me and the pump incase the tyre blows!
Once the tyre is seated drop the pressure back to a safe 40 psi and spin the wheel to spread the sealant that should help seal the Valve.

Also - 60psi seems far too high to get seated. (possible accident type pressures!) On a tubeless ready rim it will seat at a very low pressure, almost before anything registers on the gauge. I think you should check to see if a tubeless conversion kit is needed.

60psi may wreck the rim, there is usually a max of around 40 for tubeless MTB.

Take off all the tape, and clean the inside of the rim with meths really well.

Get some normal electrical tape, and use that. Apply it so it is stretched on, and only a couple of times round.

Put an X shaped cut on the valve hole.

Put a tyre on with a tube in it, and inflate. Leave for 24 hours, or even go for a ride.

Take tube out, being careful only to unseat one side of the tyre. Put tubeless valve in. Add soapy water with fingers to the unseated side of the rim. Carefully pull the unseated side of the tyre toward the rim as much as you can. Make sure not to unseat the other side.

Inflate until tyre seats (should be max 40psi).

See how long it stays up. Anything over a minute is not bad, go ahead and inject Stans. Anything less than a minute, maybe there are other problems. Where is the air coming out from?

Apologies if I'm wrong, but I believe the tubeless tapes from superstar or stans are for sealing the spoke bed of a tubeless ready rim only. The rim is already designed to firmly hold and seal the bead of a tyre at low pressures. If its not tubeless ready then you'll need a tubeless conversion kit where you get a thicker rubber strip that overlaps the entire rim to make a new seal for the tyre bead. This can be bought - eg stans or Joes, making sure you get one wide enough for your rims, or in stw style, there are various ghetto methods involving old small innertubes.

Caveat on these kits - imo, not as reliable as a tubeless ready or UST rim. I'm sure someone will be along in a bit to say they work everytime though

I set up my new flows tubless yesterday with some new bonty xr4 team issues.
The day before I fitted gorilla tape to go,two layers before wrestling on the tyres and tube.
And I mean wrestle, I have never struggled as much to get a tyre on a rim ever.

Once on it was impossible to seat even with the tube until I squirted some fenwicks bike cleaner I keep mixed in a squirty bottle around the edge of the tyre/rim before inflating with track pump which solved the problem.
I only fitted the tube to help compress the tape to ensure it was stuck down properly.

Yesterday, some more wrestling to remove tube, fit stans valves and refit the side of the tyre. Quick squirt around tyre/rims with some more fenwicks and inflated using co2 inflater then track pump to forty psi to reseat tyre.

Deflated , removed valve core before adding joes super sealant and reinflating and giving it a good shake as if panning for gold.

The only drama was the fact the tyre was really hard work to install and seat due to being tighter than a gnats chuff.
I converted my bonty tlr wheels last week using their rim strips and valves with maxxis ardent/minion tyres no trouble at all as the tyres went on easy and the co2 inflater seated them in seconds with no soap required.

Only thing I did not align valve with tyre logos on the flows as even with only one side of the tyre on it was too tight to rotate the tyre around the rim to line them up and did not want to risk damaging the gorilla tape trying .

If the tyre is holding air and friction is stopping the bead from seating, I would suggest more soap and invest in a co2 inflator or maybe run the wheels down to a petrol station and use their compressor.

I have used the plastic Bontrager rim strips with great success on non TLR rims.
They are shaped in profile to lock in the bead as well as seal the spoke holes.
I use their valves with them too.
However - easiest assembly ever were the Stans ArchEX with just SS yellow tape on. Almost like they were designed for it......

I set up my new flows tubless yesterday with some new bonty xr4 team issues.
The day before I fitted gorilla tape to go,two layers before wrestling on the tyres and tube.
And I mean wrestle, I have never struggled as much to get a tyre on a rim ever.

You sure as hell don't need 2 layers of Gorilla tape on Stans rims to seat anything. One wrap of yellow tape is more than enough.

My 29-3's went up easy as pie with one wrap of yellow tape on Crests, using a track pump

chip - Member
I used the gorilla tape because the shop where I bought the valves only had 21mm stans tape and I had a new roll of 1" gorilla tape at home. And went round twice as better safe than sorry.

That's what I use - I've never had a problem with it on Sun Ringle EQ27's, Mavic 717's,719's, 219's 321's and with any number of Schwalbe, Maxxis, Michelin, Panaracer tyres. The only tyres I gave up on were a pair of Kenda Nevegals and ten only because the sidewalls were so porous.
I regularly run low pressures (18-22 psi) too and yet now we're getting told that we should only use "tubeless rims".
What's the world coming to? - It probably is Bob Crow's fault, he was over here too, after all.